diff --git a/.travis.yml b/.travis.yml
index e049201d4..cd8fa102d 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,4 +1,4 @@
-dist: trusty
+dist: xenial
 sudo: required
 
 language: python
@@ -8,23 +8,24 @@ cache: pip
 
 before_install:
   - lsb_release -a
-  - sudo add-apt-repository ppa:deluge-team/develop -y
-  - sudo apt-get update
+  - sudo add-apt-repository ppa:deluge-team/develop -yu
 
 # command to install dependencies
 install:
   - bash -c "echo $APTPACKAGES"
-  - sudo apt-get install $APTPACKAGES
-  - pip install tox
+  - sudo apt install $APTPACKAGES
+  - pip install tox tox-venv
   # the next part is for the security tests only.
-  - wget https://github.com/drwetter/testssl.sh/archive/v2.9.5-5.tar.gz -O testssl.tar.gz
-  - tar -xvzf testssl.tar.gz
-  - mv -t deluge/tests/data testssl.sh-2.9.5-5/testssl.sh testssl.sh-2.9.5-5/etc/
+  - "if [ $TOX_ENV == 'security' ]; then
+    testssl_url=https://github.com/drwetter/testssl.sh/archive/v2.9.5-5.tar.gz;
+    wget -O- $testssl_url | tar xz
+    && mv -t deluge/tests/data testssl.sh-2.9.5-5/testssl.sh testssl.sh-2.9.5-5/etc/;
+    fi"
 
 env:
   global:
     - APTPACKAGES="python-libtorrent"
-    - APTPACKAGES_GTKUI="python-gobject python-glade2"
+    - APTPACKAGES_GTKUI="python-glade2"
     - DISPLAY=:99.0
 
 matrix:
@@ -36,7 +37,7 @@ matrix:
     #- env:  TOX_ENV=flake8-complexity
     - env: TOX_ENV=docs
     #- env: TOX_ENV=todo
-    - env: TOX_ENV=trial              APTPACKAGES="$APTPACKAGES $APTPACKAGES_GTKUI"
+    #- env: TOX_ENV=trial              APTPACKAGES="$APTPACKAGES $APTPACKAGES_GTKUI"
     - env: TOX_ENV=pygtkui            APTPACKAGES="$APTPACKAGES $APTPACKAGES_GTKUI"
     #- env: TOX_ENV=testcoverage       APTPACKAGES="$APTPACKAGES $APTPACKAGES_GTKUI"
     - env: TOX_ENV=plugins
diff --git a/appveyor.yml b/appveyor.yml
index 26a0edaec..ccc45d4dd 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -4,9 +4,7 @@ environment:
   APPVEYOR_SAVE_CACHE_ON_ERROR: true
 
   matrix:
-    # See: http://www.appveyor.com/docs/installed-software#python
     - TOXENV: flake8
-    - TOXENV: trial
     - TOXENV: pydef
     - TOXENV: pygtkui
     - TOXENV: plugins
@@ -30,23 +28,12 @@ install:
 
   - "python -m pip install --upgrade pip"
   - if defined TOXENV (
-    pip install
-    tox
-    pywin32
-    certifi
+    pip install tox tox_venv
     )
   - if not defined TOXENV (
     pip install
+    -rrequirements.txt
     slimit
-    twisted[tls]
-    chardet
-    mako
-    pyxdg
-    pillow
-    slimit
-    setproctitle
-    pywin32
-    certifi
     pygame
     bbfreeze
     pefile
diff --git a/pyproject.toml b/pyproject.toml
index 8962ece64..b6dc2444b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -2,6 +2,7 @@
 requires = [
     "setuptools",
     "wheel",
+    "slimit",
 ]
 
 [tool.black]
diff --git a/requirements-dev.txt b/requirements-dev.txt
new file mode 100644
index 000000000..d03e06313
--- /dev/null
+++ b/requirements-dev.txt
@@ -0,0 +1,16 @@
+-r requirements.txt
+-r requirements-docs.txt
+-r requirements-tests.txt
+sphinx-autobuild
+tox
+tox-venv
+detox
+pre-commit
+pre-commit-hooks
+flake8-blind-except
+flake8-builtins
+flake8-commas
+flake8-comprehensions
+flake8-debugger
+flake8-mock
+flake8-mutable
diff --git a/requirements-tests.txt b/requirements-tests.txt
new file mode 100644
index 000000000..841b68fa4
--- /dev/null
+++ b/requirements-tests.txt
@@ -0,0 +1,10 @@
+pytest
+pytest-twisted
+pytest-cov
+mock
+flake8
+flake8-quotes
+flake8-isort
+pep8-naming
+mccabe
+pylint
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 000000000..fcc1b46d3
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1,12 @@
+twisted[tls]>=16.6
+pyopenssl
+pyxdg
+pillow
+mako
+chardet
+six
+setproctitle
+pywin32; sys.platform == 'win32'
+py2-ipaddress; sys.platform == 'win32'
+certifi; sys.platform == 'win32'
+zope-interface
diff --git a/tox.ini b/tox.ini
index 936bb530d..fc008dfce 100644
--- a/tox.ini
+++ b/tox.ini
@@ -7,33 +7,28 @@
 envlist = py27, flake8, docs
 minversion=2.0
 
+[base]
+deps = -rrequirements.txt
+
 [testenv]
 install_command = pip install --ignore-installed {opts} {packages}
 passenv = DISPLAY PYTHONPATH
 setenv = PYTHONPATH = {toxinidir}
 sitepackages = True
 deps =
-    twisted[tls]
-    service_identity
-    mako
-    chardet
-    pyopenssl
-    pyxdg
-    pytest
-    pytest-twisted
-    mock
+    {[base]deps}
+    -rrequirements-tests.txt
     slimit
-    pillow
-whitelist_externals = pytest bash
-commands = {envpython} setup.py test
+whitelist_externals = pytest
 
 [pytest]
 # Hide logged warnings and errors in test output.
 log_cli_level = CRITICAL
 
-##############
+
+# ==========
 # Unit tests
-##############
+# ==========
 
 [testenv:pydef]
 commands =
@@ -72,7 +67,6 @@ commands =
 [testenv:py27]
 deps =
     {[testenv]deps}
-    py2-ipaddress
 basepython = python2.7
 commands = {[testenv:pydef]commands}
 
@@ -80,12 +74,14 @@ commands = {[testenv:pydef]commands}
 basepython = python3
 commands = {[testenv:pydef]commands}
 
-###########################
-# Code style verification
-###########################
+
+# =======================
+# Code linting
+# =======================
 
 [testenv:flake8]
-# Disable site packages to avoid using system flake8 which uses hardcoded python path which imports the wrong libraries.
+# Disable site packages to avoid using system flake8 which uses
+# hardcoded python path which imports the wrong libraries.
 sitepackages = False
 deps =
     {[testenv]deps}
@@ -121,9 +117,9 @@ commands =
     python -m pylint deluge/plugins/*/deluge/
 
 
-######################
-# Unit Test coverage
-######################
+# =============
+# Test coverage
+# =============
 
 [testcoveragebase]
 deps =
@@ -152,9 +148,9 @@ commands =
     coverage html -d docs/build/htmlcoverage
 
 
-######################
-# Docs generation
-######################
+# ===================
+# Documentation build
+# ===================
 
 # We do not have all dependencies on RTD and travis so we exclude the
 # site packages (sitepackages=False) when building docs so that local
@@ -188,3 +184,12 @@ commands =
     mkdir -p build/doccoverage
     sphinx-build -W -b coverage -d build/doctrees source build/doccoverage
     pytest --doctest-glob='*.rst'
+
+
+# ========================
+# Developement Environment
+# ========================
+[testenv:devenv]
+envdir = .venv
+usedevelop = True
+deps = -rrequirements-dev.txt